Monday, October 11, 2010

Protoavis texensis (The "first bird from Texas") is (controversially) regarded as an died out species that could be the earliest fossil of a bird, pushing back avian origins into the Late Triassic.

Protoavis is claimed to have been a foot-tall bird that lived in what is now Texas, USA, around 225 million years ago. Though it existed 75 million years previous than Archaeopteryx its skeletal structure is supposedly more bird-like. Protoavis has been reconstructed as carnivorous bird that had teeth on the tip of its jaws and eyes situated at the front of the skull; suggestive of that it may have hunted at twilight or in the dark. It had little flying ability but could almost certainly have flown up a tree.

However, this description of Protoavis assumes that Protoavis in fact existed and, if so, that it has been reconstructed correctly. Many biologists doubt Protoavis because of the circumstances of its discovery. When they were discovered at a quarry in the Texas panhandle in 1984, in sedimentary strata of a Triassic river delta, the fossils were a jumbled cache of disarticulated persons that may reflect an incident of mass mortality following a flash flood. The discoverer, Sankar Chatterjee of Texas Tech University, was persuaded that the cache of crushed bones all belonged to the same species. However, only a few parts were establishing, primarily a skull, and this has led many to consider that the Protavis fossil is chimeric, made up of more than one organism.

If it really existed, Protoavis would raise attractive questions about when birds began to diverge from the dinosaurs, but until better proof is produced, the animal's status at present remains uncertain.

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Dinosaurs Fossils

Dinosaur fossils have been known about for millennia, though their true nature was not recognized; the Chinese considered them to be dragon bones, while Europeans believed them to be the remains of giants and other creatures killed by the Great Flood.